Light mortar for fin-stabilized projectiles

ABSTRACT

This disclosure relates to a light mortar for fin-stabilized projectiles comprising a mortar barrel defined by upper and lower tubes, means for pivotally mounting the upper and lower tubes relative to each other about an axis transverse to the axis of the mortar barrel, linkage means disposed between the upper and lower tubes for imparting a relative force therebetween to pivotally move the upper and lower tubes relative to each other about the pivotal mounting means between a coaxially aligned firing position and a position of misalignment of the tube axes, a pair of support columns between the upper and lower tubes with the pivotal mounting means being in spanning relationship between the support columns, the linkage means also being disposed between the support columns and including a toggle system having bell crank means for imparting the relative force to pivotally move the upper tube relative to the lower tube, and a half-shell supported by the support columns adjacent an upper end of the lower tube with means for locking a lower end of the upper tube to the latter-mentioned half-shell.

'United States Patent [191 Asikainen 451 July 1, 1975 LIGHT MORTAR FOR FIN-STABILIZED PROJECTILES [75] Inventor: Niilo Klaervo Asikainen, Tampere,

Finland [73] Assignee: Oy Tampelle AB, Tampere, Finland [22] Filed: July 26, 1973 [2]] Appl. No.1 382,940

[56] References Cited UNITED STATES PATENTS 2,790,357 4/1957 Garrett 89/37 C FOREIGN PATENTS OR APPLICATIONS France 89/37 C United Kingdom 89/37 C Primary Examiner-Stephen C. Bentley Attorney, Agent, or FirmDiller, Brown, Ramik & Wight [57] ABSTRACT This disclosure relates to a light mortar for finstabilized projectiles comprising a mortar barrel defined by upper and lower tubes, means for pivotally mounting the upper and lower tubes relative to each other about an axis transverse to the axis of the mortar barrel, linkage means disposed between the upper and lower tubes for imparting a relative force therebetween to pivotally move the upper and lower tubes relative to each other about the pivotal mounting means between a coaxially aligned firing position and a position of misalignment of the tube axes, a pair of support columns between the upper and lower tubes with the pivotal mounting means being in spanning relationship between the support columns, the linkage means also being disposed between the support columns and including a toggle system having bell crank means for imparting the relative force to pivotally move the upper tube relative to the lower tube, and a half-shell supported by the support columns adjacent an upper end of the lower tube with means for locking a lower end of the upper tube to the latter-mentioned half-shell.

10 Claims, 9 Drawing Figures PATENTEDJUL 1 i975 SHEU FIG. 1

LIGHT MORTAR FOR FIN-STABILIZED PROJECTILES The present invention is directed to a light mortar for tin-stabilized projectiles in which the mortar barrel is mounted on a base plate and is supported between its extremities upon a pivotal stand or carriage.

In general, the angle of elevation of the barrel of a light mortar is relatively steep to enable the weapon to be muzzle-loaded by gravity. The projectile slides downward toward the base or breech at which the propellant charge is ignited by a firing pin mechanism located at the base resulting in the propulsion of the projectile outwardly of the mortar barrel toward a desired target.

As the caliber of the mortar increases. the barrel lengthens in proportion so that difficulties arise in employing muzzle-loading where the barrel mouth is at a relatively high elevation. In order to facilitate loading it is common practice to in effect divide the mortar barrel into two barrel portions of approximately the same length. In such cases, the lower barrel portion or tube is pivoted for engagement and disengagement about a transverse axis generally in the area of the closed breech with the two barrel portions being locked together by suitable guide and also by a releasable gastight coupling mechanism. In mortars of this construction, the same are loaded through the muzzle of the lower barrel portion. Thus, when the mortar barrel is inconveniently long loading is not carried out with desirable comparative ease.

It is to be noted that when loaded through the lower barrel portion the missile slides downward toward the breech during which the barrel portions begin to close and upon closing the firing pin mechanism is actuated. In such an arrangement there is, obviously, a risk of premature ignition, that is to say, a failure in the firing pin mechanism which will lead to detonation of the propellant charge before the mortar barrel portions are closed and in fact remain partially disengaged. Such premature detonation is obviously much more serious than in the case of an integral one-piece mortar barrel because the premature ignition of the projectile is directed at the division between the barrel portions and upon striking the upper portion which is disposed at an angle to the lower portion the mortar would become totally unserviceable, if not actually destroyed, by virtue of the detonation of the projectile.

In keeping with the foregoing a primary object of this invention is to provide a light mortar for fin-stabilized projectiles in which known advantages attributed to longer barrel lengths are retained together with a more convenient loading by constructing the mortar barrel in a pair of pivotally attached tubes with the manner of opening and closing being such that the disadvantage of premature ignition of the projectile when the two tubes are disengaged is obviated. The mortar of the invention is characterized by a construction such that the upper tube or upper barrel portion may be swivelled outwardly from the lower barrel portion or lower tube about a generally transverse axis relative to the mortar barrel axis and the cooperative pivoting action is achieved by linkage means through an operating device which includes a bell crank mechanism operative through an arm to ope rate a latch to maintain the upper and lower tubes in axial alignment.

Due to the safe construction of the mortar of this invention the same may be loaded by way of the upper tube and not from above but from beneath. That is, the projectile is inserted nose first into the lower opening of the upper mortar tube in the normal manner in which such projectiles are loaded, that is to say at handheight, and only after the two tubes have been closed into coaxial alignment is it possible for the projectile to slide down into the lower tube into the breech where the firing pin mechanism can become operative. lf during the sequence a premature ignition should occur, i.e. the firing pin mechanism acts prematurely, the two mortar tubes are in closed position and the projectile will leave the mortar barrel as in the case of a normal one piece or integral barrel, except that the event (launching) is immature in that, for example, the sighting, aiming or the like of the mortar may not have been completed. Since detonation due to premature firing does not cause destruction of the mortar itself or to persons adjacent thereto is not involved and the only unpleasant consequence is the likelihood of the projectile being off course or off target.

A further advantage of a mortar constructed in accordance with this invention is the fact that the lower mortar tube is not swivelled outwardly of the mortar base plate to disengage these two parts in a conventional manner but instead as a rigid platform relative to which only the upper mortar tube is swivelled or pivoted. This type construction is also less expensive to produce than that which requires the lower mortar tube to be disengaged from the mortar base during loading operations. Finally, the present invention permits the use of mortar barrels of much greater length and larger calibers, for example, in excess of mm. In effect, the mortar of this invention provides a much longer barrel than heretofore possible under similar circumstances of loading, relatively slow burning powder may be used as the propellant, higher muzzle velocities are obtained, and the rate of fire is increased.

With respect to the specific mechanisms of the mortar, the earlier mentioned linkage means includes a pair of rods or columns bridged by a transverse pivot pin pivotally carrying the upper mortar tube with the lower ends of the columns being joined to an upper end portion of the lower mortar tube. The linkage and operating mechanisms are preferably located between these columns and columns are also constructed as recoil absorbers for the mortar.

The linkage mechanism further preferably includes a toggle arrangement of levers including a bell crank which is operative to a bracket secured to the upper mortar tube for swivelling the same between its coaxially aligned and unaligned positions relative to the lower tube. The same linkage mechanism further includes a link which operates a spring catch for locking the two mortar barrels in their closed position in complete axial alignment. In addition, additional locking means are provided for the upper and lower mortar tubes through the use of a half-shell mounted upon the earlier mentioned columns with the half-shell receiving a lower end portion of the upper mortar tube and being interlocked by cooperative inner locking groove and ring means through a manually operable locking stud.

In further keeping with this invention means are provided to prevent a bomb or projectile which has been inserted into the lower end of the upper mortar tube while the two tubes are not fully closed or in perfect coaxial relationship. This is preferably achieved by claw means carried by locking sleeve which projects into the interior of the upper mortar tube when the tube is disengaged but is retracted sufficiently for the bomb to slide down into the lower mortar tube as soon as coax ial alignment is achieved upon the complete closing of the upper and lower mortar tubes.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claim subject matter, and the several views illustrated in the accompanying drawings.

In the drawings:

FIG. 1 is a side elevational view of a novel light mortar for fin-stabilized projectiles constructed in accordance with this invention, and illustrates upper and lower mortar tubes in coaxial alignment defining a mortar barrel supported at one end by a base and immediately thereof by a support or carriage joined by a pivot axis to a pair of columns which are in turn pivotally connected to the upper mortar tube.

FIG. 2 is a side elevational view of the novel light mortar of this invention, and illustrates a linkage mechanism between the columns and a lower end portion of the upper mortar tube for pivotally or swivelly opening and closing the same between coaxially aligned and unaligned positions relative to the lower mortar tube.

FIG. 3 is a front elevational view partly in section of the pair of columns. and illustrates the manner in which the same are constructed as recoil absorbers for the mortar.

FIG. 4 is a side elevational view of the columns of FIG. 3, and illustrates further details thereof.

FIG. 5 is a side elevational view partially in section of linkage means in part carried by a half-shell secured to the columns and being operative to latch the upper mortar tube to the half-shell through a spring biased catch operative through a bell crank.

FIGS. 6 and 7 are large fragmentary views illustrating the manner in which the upper and lower mortar tubes are respectively disengaged and engaged through the operation of the linkage means.

FIGS. 8 and 9 are respective plan and side elevational views of claw means for maintaining a projectile housed within the lower end of the uppermost mortar tube prior to the complete closure thereof relative to the lower mortar tube.

A novel light mortar for fin-stabilized projectiles or bombs constructed in accordance with this invention is shown in its respective closed and opened positions in FIGS. 1 and 2 and is generally designated by the reference numeral 1. The mortar 1 includes a barrel 2 having a lower tube or barrel portion 10 carrying a ball 3 cooperating with a socket 4 in a base plate 5. The bar rel 2 includes a carriage or stand 6 terminating at its lower pointed extremity 7 in a plate-like collar. An upper barrel portion or upper tube 9 of the barrel 2 is connected to means 11 which includes linkage to be described hereinafter by a pivot 21 and the same link age 11 is further joined to the carriage 6 by the pivot 8.

A collar 14 embraces the upper portion of the lower tube 10 and is rigidly secured to the lower ends of the columns 12 and 13 whereas the upper ends of the columns 12, 13 are also provided with a collar 15 which includes an extension (unnumbered) embracing the pivot pin 8 of the carriage 6. In this manner, the lower tube 10 is connected to the carriage 6 through the pivot 8 whereas the upper tube 9 is likewise pivotally secured between the columns 12, 13 by the pivot pin 21.

Referring particularly to FIGS. 3 and 4, the columns 12 and 13 are interconnected at their upper ends by transverse bridging means 16 which is an element fitted by means of sleeves 17 and 18 over the columns 12, 13. The bridging element 16 includes an extension 19 carrying a sleeve 20 which mounts therein the pin 21 for pivoting the upper tube 9 to the carriage 6 in the manner best illustrated in FIGS. 1 and 2. Preferably. a collar 23 embracing the upper tube 9 carries a bearing 24 which is pivotally mounted upon the pin 21 to permit the upper tube 9 to be swivelled about the pivot pin 21 between the positions illustrated in FIGS. 1 and 2.

In order to control the pivoting or swivelling action illustrated in FIGS. 1 and 2, means 25 is provided including linkage means 26 (FIG. 5) having a pair oflinks 26a, 26b pivotally secured at 27 to brackets (unnumbered) carried by the columns 12, 13. A link 28 is pivotally connected to the link 26a and engages a toggle 29 pivotally mounted at 30 to a bracket 31 fixedly secured or integrally formed with a collar 32 embracing and secured to the upper tube 9 (FIG. 2). The link 28 is provided with a cross pin 33 which engages in a slotted hole 34 of the bracket 31. A rod 35 is connected to the apex of the toggle 29 and carries at its lower end a catch 36 secured by a pin 37 with the catch 36 being normally biased downwardly by a compression spring 38 to its latched or locked position (FIG. 5). In the latch position the catch 36 engages a fixed stop 39 supported between the columns l2, 13 (FIG. 3). The catch 36 preferably includes a bevelled shoulder 360 so that it automatically slides into engagement over the stop 39 (FIG. 5) when the upper tube is pivoted to its closed or coaxial position (FIG. I). A suitable collar 35a surrounding the rod 35 supports the spring within a housing (unnumbered) of the collar 32 in the manner readily apparent from FIG. 5.

The link or arm 26b is intended as a hand lever and is pressed downward or clockwise from the position shown in FIG. 2 to the position shown in FIG. 1 when it is desired to bring the tube 9 into coaxial relationship with the tube 10 and vice versa when it is desired to bring the tubes 9, 10 from the coaxial position of FIG. I to that of non-alignment in FIG. 2.

The lower end of the upper mortar tube 9 carries a locking sleeve 40 which may be rotated by means of a manually operable stud 41. On the upper portion of the locking sleeve 40 grooves 42 and rings 43 are provided which engage corresponding rings 44 and grooves 45 on the half-shell 46 when the tube 9 is in its closed position, it being noted that the half-shell 46 spans and is secured to the columns 12, 13. The half-shell is secured to the columns 12 and 13 by means of sleeves 47 and 48. Thus, when the upper tube 9 is closed the locking stud 41 engages in a notch 49 on a lateral face (unnumbered) of the half-shell 46 and at the same time the stop 39 latches and retains the catch 36 in the position shown in FIG. 5.

The locking sleeve 40 is connected by means of a rod 50 to the collar 23 embracing the upper mortar tube 9 which also carries the pivot 21. The upper tube 9 may be displaced to a limited extent within the collar 23 and the locking sleeve 40 in order to assure a tight joint be tween the two tubes in the closed position. FIGS. 6 and 7 illustrate the sealing of the upper tube 9 against the lower tube 10 when the barrel 2 is closed. The tube 9 preferably includes on its end face a raised rim 9a which engages a corresponding annular groove 10a in the lower tube 10. A sealing ring 53 is housed in the lower tube 10 and after the two tubes 9, 10 have been returned to alignment continued downward pressure upon the handle 26 beyond the point of contact of the tubes produces a certain longitudinal displacement of the upper tube 9 through the collar 31 so that the raised rim 9a is pressed into engagement with the annular groove 10a and behind the sealing ring 53. This slight movement is permitted due to a slotted hole 51 (FIG. 2) being formed in the collar 23 at diametrically opposite sides thereof within which is received an associated stud 52 affixed to the upper tube 9. Due to this limited longitudinal movement the two end faces of the upper and lower tubes 9, 10 are tightly coupled together. The rings 43 of the locking sleeve 40 engage in the annular grooves 45 of the half-shell 46 so that the locking stud 41 enters the notch 49 of the half-shell 46. When the projectile is fired the tightness of these joints is simply reinforced thereby.

In order to disengage the tubes from their axial alignment the handle 26 is raised from the position shown in FIG. 1 to the position shown in FIG. 2 so that the rim 9a is first retracted from the annular groove 10a of the lower tube 10 and upon further upward pressure on the handle 26 the catch 39 is disengaged and the upper tube is then swivelled or pivoted outwardly to the position shown in FIG. 2.

Reference is now made to FIGS. 8 and 9 which illustrates means in the form of a claw 54 at an end face of the locking sleeve 40 for retaining the projectile or bomb in the upper tube 9 when inserted therein through the bottom. The claw 54 projects into the interior of the upper tube 9 and is pivotally mounted in a flange S5 of the locking sleeve 40. Preferably the claw 54 is biased by a spring or the like to which projected position (FIG. 8) by a spring 56. Thus when the upper tube 9 reaches its closed position the claw 54 is pressed back against the pressure of the spring 56 so that, when the tube barrels or tubes 9, 10 are locked together, the claw 54 no longer projects into the interior of the tube 9 and the projectile earlier loaded thereinto will slide down into the lower tube 10 under the influence of gravity toward the base 5 and the firing pin mechanism within the lower end of the tube 10.

Though not necessarily required the columns l2, 13 (FIG. 3) are further constructed as recoil-absorbing elements. For this purpose the columns 12, 13 are of a tubular construction and each contains a further tube 57 displaceable telescopically therewithin. The tube 57 acts upon shock-absorbing springs 58 resting on a fixed abutment 59.

While preferred forms and arrangements of parts have been shown in illustrating the invention, it is to be clearly understood that various changes in details and arrangement of parts may be made without departing from the spirit and scope of this disclosure.

I claim:

I. A light mortar for projectiles comprising a mortar barrel defined by upper and lower tubes of generally equal length, said upper and lower tubes having upper and lower ends, a base plate at the lower end of said lower tube, rigid support means connected to the upper end of said lower tube and projecting therebeyond, at

least a single supporting leg, first means pivotally mounting said leg to said rigid support means whereby the inclination of said lower tube can be selectively varied dependent upon the angle included between said lower tube and said supporting leg, second means pivotally mounting said upper tube between its upper and lower ends to said rigid support means for pivoting movement about an axis transverse to the axis of said mortar barrel thereby providing relative pivotal movement between said upper and lower tubes, said second pivot means being located between said first pivot means and the upper end of said lower tube, linkage means connected to said rigid support means between said second pivot means and said lower tube upper end, said linkage means being farther connected to said upper tube lower end for moving the upper tube into and out of coaxial relationship with said lower tube, and means at the upper tube lower end for preventing a projectile inserted therein from falling by gravity into said lower tube when said upper and lower tubes are not coaxially aligned and until such time as said upper and lower tubes are in coaxial relationship.

2. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes with said pivotal mounting means being in spanning relationship between said support columns.

3. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes with said linkage means being disposed between said support columns.

4. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes with said second pivotal mounting means being in spanning relationship between said support columns and said linkage means being disposed between said support columns.

5. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes, and said columns include means for absorbing recoil during the firing of said mortar.

6. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes, a half-shell supported by said support columns adjacent the upper end of said lower tube, and means for locking the lower end of said upper tube to said half-shell.

7. The light mortar as defined in claim 1 wherein said rigid support means include means for straight line displacement of said upper and lower tubes relative to each other parallel to the barrel axis when the tube axes are coincident.

8. A light mortar for projectiles comprising a mortar barrel defined by upper and lower tubes of generally equal length, said upper and lower tubes having upper and lower ends, a base plate at the lower end of said lower tube, at least a single supporting leg, means pivotally mounting said leg to said upper tube between the upper and lower ends thereof and about an axis transverse to the axis of said mortar barrel whereby said upper and lower tubes are likewise mounted for relative pivotal movement about said transverse axis, support means connected between the upper end of said lower tube and to said upper tube between the upper and lower ends thereof, linkage means between said support means and said upper tube lower end for moving said upper tube into and out of coaxial relationship with said lower tube, means at the upper tube lower end for preventing a projectile inserted therein from falling by gravity into said lower tube when said upper and lower tubes are not coaxially aligned and until such time as said upper and lower tubes are in coaxial relationship, said linkage means includes a handle, means mounting said handle to said support means for pivotal movement relative thereto, means for locking said tubes to each other in coaxial relationship. and means connected between said linkage means and said locking means for unlocking the latter upon motion imparted to said handle.

9. A light mortar for projectiles comprising a mortar barrel defined by upper and lower tubes, means for pivotally mounting said upper and lower tubes relative to each other about an axis transverse to the axis of said mortar barrel, linkage means disposed between said upper and lower tubes for imparting a relative force therebetween to pivotally move said upper and lower tubes relative to each other about said pivotal mounting means. and said linkage means includes a toggle system having bell crank means for imparting said relative force to pivotally move said upper tube.

10. The light mortar as defined in claim 9 including latch means operative through said linkage means for latching said upper and lower tubes in axial alignment i i 

1. A light mortar for projectiles comprising a mortar barrel defined by upper and lower tubes of generally equal length, said upper and lower tubes having upper and lower ends, a base plate at the lower end of said lower tube, rigid support means connected to the upper end of said lower tube and projecting therebeyond, at least a single supporting leg, first means pivotally mounting said leg to said rigid support means whereby the inclination of said lower tube can be selectively varied dependent upon the angle included between said lower tube and said supporting leg, second means pivotally mounting said upper tube between its upper and lower ends to said rigid support means for pivoting movement about an axis transverse to the axis of said mortar barrel thereby providing relative pivotal movement between said upper and lower tubes, said second pivot means being located between said first pivot means and the upper end of said lower tube, linkage means connected to said rigid support means between said second pivot means and said lower tube upper end, said linkage means being farther connected to said upper tube lower end for moving the upper tube into and out of coaxial relationship with said lower tube, and means at the upper tube lower end for preventing a projectile inserted therein from falling by gravity into said lower tube when said uppEr and lower tubes are not coaxially aligned and until such time as said upper and lower tubes are in coaxial relationship.
 2. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes with said pivotal mounting means being in spanning relationship between said support columns.
 3. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes with said linkage means being disposed between said support columns.
 4. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes with said second pivotal mounting means being in spanning relationship between said support columns and said linkage means being disposed between said support columns.
 5. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes, and said columns include means for absorbing recoil during the firing of said mortar.
 6. The light mortar as defined in claim 1 wherein said rigid support means include a pair of support columns between said upper and lower tubes, a half-shell supported by said support columns adjacent the upper end of said lower tube, and means for locking the lower end of said upper tube to said half-shell.
 7. The light mortar as defined in claim 1 wherein said rigid support means include means for straight line displacement of said upper and lower tubes relative to each other parallel to the barrel axis when the tube axes are coincident.
 8. A light mortar for projectiles comprising a mortar barrel defined by upper and lower tubes of generally equal length, said upper and lower tubes having upper and lower ends, a base plate at the lower end of said lower tube, at least a single supporting leg, means pivotally mounting said leg to said upper tube between the upper and lower ends thereof and about an axis transverse to the axis of said mortar barrel whereby said upper and lower tubes are likewise mounted for relative pivotal movement about said transverse axis, support means connected between the upper end of said lower tube and to said upper tube between the upper and lower ends thereof, linkage means between said support means and said upper tube lower end for moving said upper tube into and out of coaxial relationship with said lower tube, means at the upper tube lower end for preventing a projectile inserted therein from falling by gravity into said lower tube when said upper and lower tubes are not coaxially aligned and until such time as said upper and lower tubes are in coaxial relationship, said linkage means includes a handle, means mounting said handle to said support means for pivotal movement relative thereto, means for locking said tubes to each other in coaxial relationship, and means connected between said linkage means and said locking means for unlocking the latter upon motion imparted to said handle.
 9. A light mortar for projectiles comprising a mortar barrel defined by upper and lower tubes, means for pivotally mounting said upper and lower tubes relative to each other about an axis transverse to the axis of said mortar barrel, linkage means disposed between said upper and lower tubes for imparting a relative force therebetween to pivotally move said upper and lower tubes relative to each other about said pivotal mounting means, and said linkage means includes a toggle system having bell crank means for imparting said relative force to pivotally move said upper tube.
 10. The light mortar as defined in claim 9 including latch means operative through said linkage means for latching said upper and lower tubes in axial alignment. 